<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>class选择器</title>
    <style type="text/css">
        .class01,#id001 {
            color: blue;
            font-size: 30px;
            border: 1px solid yellow;
        }
        .class02{
            color: gray;
            font-size: 20px;
            border: 1px solid red;

        }
    </style>
</head>
<body>
     <div class="class01">div标签class01</div>
     <div>div标签</div>
     <span class="class02">span标签</span>
     <span>span标签</span>
</body>
</html>